In addition to the notion of "breaking through" defense mechanisms, other metaphors were adopted by practitioners relating to the supposed effects of early deprivation, abuse or neglect on the child's ability to form relationships. These included the idea of the child's development being "frozen" and treatment being required to "unfreeze" development. Practitioners of holding therapy also added some components of Bowlby's attachment theory and the therapy came to be known as attachment therapy. Language from attachment theory is used but descriptions of the practices contain ideas and techniques based on misapplied metaphors deriving from Zaslow and psychoanalysis, not attachment theory. According to Prior and Glaser "there is no empirical evidence to support Zaslow's theory. The concept of suppressed rage has, nevertheless, continued to be a central focus explaining the children's behavior." Cline's privately published work Hope for high risk and rage filled children also cites family therapist and hypnotherapist Milton Erickson as a source, and reprints parts of a case of Erickson's published in 1961. The report describes the case of a divorced mother with a non-compliant son. Erickson advised the mother to sit on the child for hours at a time and to feed him only on cold oatmeal while she and a daughter ate appetizing food. The child did increase in compliance, and Erickson noted, with apparent approval, that he trembled when his mother looked at him. Cline commented, with respect to this and other cases, that in his opinion all bonds were trauma bonds. According to Cline, it illustrates the three essential components of 1) taking control, 2) the child's expression of rage; and, 3) relaxation and the development of bonding. In addition, proponents believed that holding induced age regression, enabling a child to make up for physical affection missed earlier in life. Regression is key to the holding therapy approach. In attachment therapy, breaking down the child's resistance by confrontational techniques is thought to reduce the child to an infantile state, thus making the child receptive to forming attachment by the application of early parenting behaviors such as bottle feeding, cradling, rocking and eye contact. Some, but by no means all, attachment therapists have used rebirthing techniques to aid regression. The roots of the form of rebirthing used within attachment therapy lie in primal therapy (sometimes known as primal scream therapy), another therapy based on beliefs in very early trauma and the transformational nature of age